(22-Jan) -- Today was a very big day for three-time Olympian Deena Kastor,
as the 39-year-old from Mammoth Lakes, Calif., was announced to be running
both the USA National Cross Country Championships on February 2, as well as
the LA Marathon on March 17.

Kastor has had great success over her career in cross country, having won a pair
of IAAF World Cross Country Championships silver medals in 2002 and 2003. The mother
of one daughter has also taken home top honors at the USA Cross Country National Championships
seven times; her most recent title came back in 2007, when she defeated Shalane Flanagan and
Kara Goucher for the win.

This year's National Cross Country Championships are to be run in St. Louis's Forest Park, home of the 1904 Olympic Games and World's Fair. Kastor has had good
luck in St. Louis before --in 2004, prior to earning a bronze medal at the Olympic Marathon, Kastor placed second at the U.S. Olympic Marathon Trials there.

Nearly a month and a half after the USA Cross Country Championships, Kastor will again toe the line, this time in her home state for the LA Marathon. The
American record holder for the marathon, Kastor's personal best for the distance is 2:19:36, which she ran at the 2006 London Marathon.

"I was on the LA Marathon course last year as part of the broadcast team, and I was so impressed with the course and the energy of the event that I knew I needed
to compete in 2013," said Kastor in a statement from race organizers. "I am really looking forward to running the Stadium to the Sea route alongside thousands
of other runners, including some of the world's greatest marathoners."

Kastor's last marathon came in January of 2012, when she finished sixth (2:30:40) at the U.S. Olympic Marathon Trials in Houston. This will be her first
LA Marathon; an American woman hasn't won the event in 19 years.

"Deena is the most accomplished female American distance runner in history, and to have her on the start line of the 2013 LA Marathon is tremendous," said
LA Marathon race director, Nick Curl. "We believe that having an outstanding field of runners is part of creating a world-class race and delivering a top-tier
experience for all participants."

Kastor did one more notable thing on Tuesday: she joined Twitter. Kastor's Twitter handle is @DeenaKastor, and she already has nearly 600 followers. Her first
tweet was, "Great XC style workout at Millpond today while a bald eagle observed from a nearby tree!"

PHOTO: Deena Kastor holds daughter Piper at the New York Road Runners Olympic Trials barbeque in Eugene, Ore., last summer